Many people take anticoagulants to maintain the theropedic coagulation time of their blood. Depending upon the person, the peak anticoagulant effect of the anticoagulant may be delayed by many hours and/or days, and the duration of the effect may persist after the peak for another four to five days. Accordingly, it is critical that the people who take anticoagulants closely monitor the coagulation time of their blood, so that they can monitor and adjust the amount of the anticoagulant they are taking.
A common manner of determining the effective amount of anticoagulant in a person's blood is to perform a prothrombin time (PT) test. A PT test measures how long a sample of blood takes to clot. As a result, the anticoagulation or hemostasis level in the blood is directly proportional to the length of time required to form clots.
Many devices and apparatus exist for performing coagulation time measurements and tests. Some of these apparatus are portable and simple enough to operate by a person in his or her home. An example of such an apparatus is describe in U.S. Pat. No. 5,534,226, entitled PORTABLE TEST APPARATUS AND ASSOCIATED METHOD OF PERFORMING A BLOOD COAGULATION TEST, issued to Gavin et al. and assigned to International Technidyne Corporation, the assignee herein. The apparatus described in this patent includes a disposable cuvette and a testing device. In operation, a sample of blood is placed into a cup-like supply reservoir of the cuvette, the blood sample is drawn into the cuvette, and the coagulation time of the blood sample is measured.
A problem associated with such apparatus, is that the volume of the blood sample drawn into the cuvette for measurement and testing is controlled by both the testing device and the sample cup removal techniques. Moreover, the cup-like supply reservoir can be messy to use.
Accordingly, a need exits for an improved apparatus for measuring and testing blood coagulation.